1. Field of the Invention
The invention relates generally to detection and analysis of contaminant in soil and particularly to a method and apparatus for on-site determination of the type, location and quantity of contaminant in soils by measurement of the spectral signature of the soils.
2. Description of the Prior Art
Soil contamination studies must periodically be conducted at hazardous waste sites and are also conducted in other situations where soil contamination is suspected. Such studies have typically involved the use of a soil auger to dig a hole to a desired depth for sampling. A tube sampler is then pushed or hammered into the bottom of the auger hole to obtain the sample which must then be extracted from the sampler, packed for shipping and then sent to a suitable laboratory facility for characterization of any contaminants present in the soil sample. The auger is then used once again after extraction of the first sample to clean out and deepen the sampling hole with the entire sampling process then being repeated. This prior art procedure is notoriously slow, and does not produce a continuous record of contaminant distribution in the soil. As is apparent, this prior art process only produces an intermittent record of contaminant distribution and further requires a very substantial amount of time not only to take the samples but to put together an analysis of the samples. Further, due to the possibility of contaminants being present in the soil being tested, the auger cuttings require special handling. The tube samplers must also be cleaned after each use so as not to contaminate subsequent samples. Analysis of the samples requires a substantial amount of time and delay due to the necessity for laboratory work. Field sampling must often be repeated in the prior art process when laboratory analyses prove faulty or if errors in sampling occur. The prior art has not previously provided the ability to produce a continuous record of contaminant distribution in soil and certainly has not provided the ability to produce such a continuous record in real time and on site. The present invention provides such capability and further produces no waste material which must be disposed of and does not expose test personnel on site to samples of contaminated soil. The invention further eliminates the requirement for the packing and shipping of soil samples to a laboratory for analysis along with the resultant delays. Since soil contamination can be immediately detected during testing, test personnel can effect changes in the testing procedure as necessitated by the data being collected in real time.